Cub born to giant panda at National Zoo

FILE - In this Dec. 19, 2011 file photo, Mei Xiang, the female giant panda at the Smithsonian's National Zoo in Washington, eats breakfast. Mei Xiang has given birth to a cub following five consecutive pseudopregnancies in as many years. (AP Photo/Susan Walsh)

WASHINGTON (AP) — A giant panda at Washington's zoo surprised scientists and zookeepers by becoming a mom again after years of failed pregnancies.

Scientists at the zoo had all but given up on 14-year-old Mei Xiang's chances of conceiving, but they were watching the panda for a possible cub nonetheless after she was artificially inseminated earlier this year. She gave birth late Sunday, her first cub since 2005.

Like all newborn pandas, the cub is pink, hairless and about the size of a stick of butter. Officials will follow Chinese custom and give it a name after 100 days.

Four American zoos have pandas, but Washington's pandas have special significance. The zoo was given its first set of pandas in 1972 as a gift from China to commemorate President Richard Nixon's historic visit to the country.

Mei Xiang and her mate Tian Tian, were born in China and are the second pair of pandas to live at the zoo. They're treated like royalty, and any offspring gets immediate star status.

"There's something very special here with our pandas," said giant panda curator Brandie Smith. "Everyone is part of our family. We, Washington, D.C., have had a baby panda cub."

Mei Xiang gave birth to her first and only other cub, a male named Tai Shan, in 2005. Since 2007, zoo officials have had five unsuccessful attempts at artificially inseminating Mei Xiang. Each time, she went through what is called a "pseudopregnancy," building a nest and experiencing high hormone levels. But each time there was no cub.

Scientists at the zoo worried she had become infertile and believed there was a less than a 10 percent chance she would become pregnant after so many failed attempts. As a result, they had considered replacing Mei Xiang or 15-year-old Tian Tian with other pandas.

Still, there was hope.

Laurie Thompson, one of the about half a dozen panda keepers at the zoo, said each of the keepers gave Mei Xiang a pep talk.

"I know you can do this. You need to prove them wrong. You need to have a baby this year," she said she told Mei Xiang, who she has worked with since 2000.

Thompson said she got a telephone call Sunday night from another keeper. "I think I hear a panda cub," the keeper said. A small group then got on their computers to watch the zoo's panda cam. Sure enough, there was the unmistakable bird-like screech of a cub.

For now, keepers said, Mei Xiang is doing well and responding to the cub's fussy grunt and high-pitched squeal. So far, there have only been fleeting glances of the cub and it's not clear what sex it is. But keepers will continue to watch the two on camera, the same view the public has online, and won't step in unless necessary.

Keepers will likely do their first exam in three to four weeks, and it will be several months before the public can see the cub in person.

Zoo director Dennis Kelly said officials expect the newborn will bring an additional 250,000 to 500,000 visitors to the zoo over the next year. That's on top of the 2 million visitors the zoo already receives annually.

Under an agreement with the Chinese government, zoo officials can keep the cub for four years before it has to go back to China, just as its older brother Tai Shan did in 2010.

Still, there's some danger for the cub, especially in the next two weeks. Pandas have accidentally crushed their small cubs. And the zoo's first panda couple, Ling-Ling and Hsing-Hsing, had five cubs, but none of them survived more than a few days.

Zoo officials said this cub's cries sound strong, however. They plan to name it Dec. 24.

For now, however, there's a glow of amazement after "hoping and hoping and hoping for all these years," said Marty Dearie, another zoo panda keeper. There are only a few hundred pandas in captivity and about 1,600 left in the wild.